Caliper



1946- -J. c. OLOUGHLIN CALIPER Filed March 11', 1944;

v INVENTOR James C. :0Lau

9/7/17? by Marian E aloe/9k I/n, Guard/an ATTORNEY Patented Feb. 5, 1946 CALIBER James C. OLoughlin, incompetent,

Calif., by Marion F. OLoughlin,

wood City, Calif.

Redwood City, guardian, Red- Application March 11, 1944, Serial No. 526,024 7 Claims. (01. 33-165) The invention relates to calipers, and particularly to micrometer calipers.

The primary object of the invention is the provision of low cost micrometer caliper for measuring distances beyond the limited range of the fixed frame type of caliper or calipergage.

Secondar objects include the provision in a long span caliper, of means for setting the spindles in alignment, means for the correction of lateral deviation of the spindles, and means for readily adapting the tool for use over a wide range of dimensions.

The invention possesses other objects and features of value, some of which with the foregoing will be set forth in the following description of the invention. It is understood that the invention is not limited to the showing made by the said description and the drawing as variant forms of the invention within the scope of the appended claims may be adopted.

Referring to the drawing:

Figure 1 is a plan view of the calipers as the tool would appear lying on a bench. Because of the size of the complete figure, a portion of each of the frame arms is omitted.

Figure 2 is a sectional view of the left arm of the caliper, the plane of section being indicated by the line 2-2 of Figure 1.

Figure 3- is a side view of one of the caliper heads, showing both the adjusting rod and the tail spindle in section. The direction from which the view is taken is indicated by the arrow 3 of Figure 1.

In the modern machine shop which handles large and heavy work, securing accurate dimensions within tolerances common in small manufacturing, has posed a problem which increases when measurements of several feet, accurate to thousandths of an inch are required. Accurate devices of high cost are available to the large plant, but for the small shop, make-shift rigs and cut-and-try methods have been the only recourse.

In broad terms the present invention is embodied in a frame comprising two arms, each of which at one end is releasably pivoted to any one of a series of connecting links which are interchangeable to vary the capacity of the caliper. At the other or free end of each arm, a head block is adjustably mounted; and in these blocks are disposed the tail spindle or anvil and the caliper head. Means are provided on one of the frame arms for correcting any lateral deviation which may be found in the alignment of the spindles.

In terms of greater detail, the caliper of the present invention comprises two preferably range of usefulness to the tool; and their length between pivotal centers may vary from 3 inches to several feet. For example with 15 inch arms a 3 inch link gives a range up to around 24 inches either inside or outside measurement; a

24 inch link increases the capacity up to around 48 inches; while an 8 foot link would capacity from 6 feet to 10 feet. I

The links of different lengths are interchangeable; and for that reason the pivot connection between link and arm is preferably secured by means of a screw l2, preferably of the socket head type, threaded into one side of the link so that it may be tightened to rigidly lock the parts together. This construction is shown in the lower part of Figure 3 in connection with another portion of the tool.

At the free or narrower end of the arms-are pivotally mounted the head blocks l3 and M in which respectively the tail spindle or anvil l6 and the caliper head, generally designated by the reference number 11, are arranged. Each block is bifurcated at the pivoted end and a socket head screw l 8 threaded into one side, as shown in Figure 3, completes the connection. Here too, the pivoted joint may be made rigid after adjustment by tightening the screw.

The outer end of each block is preferably rounded over as shown, and bifurcated. The bottom of the bifurcating slot in the block I3 is bored to receive the tail spindle or anvil l 5, having its inner end I 9 flat, and its outer end 26 rounded, to adapt it for outside and inside measurement as is common practice in micrometer caliper construction. A set screw 22 through the separated ends of the block permits adjustment and rigid fixing of the anvil in place.

In the other block, a similar construction is used, the screw 23 clamping in the head, the sleeve 24 of the caliper head IT. The detail construction of the caliper head forms no part of the present invention since such devices are known; and it is intended that this unit will be secured from the manufacturer of such devices and as sembled in the block. It need be pointed out only that the spindle 26 extends through the device to present a fiat end 21 on the inside and a give a so thatdn .case of; needgthe flat ends l9and 2|- may be on the outside of the tool. This result of course may also be obtained without disturbing;

the clamp screws, by swinging the frame arms around on the link, through approximately 180 degrees from the positions shown ,in Figure, 1.

Means are provided for axially'aligning th'e.

caliper head spindle 26 and the anvil l6. Across the side of each head block is a groove 3 I parallel to the spindle axis. Thegrooves'a'redimem sioned to receive with a close fit, an adjusting;-

rod 32. When the rod is disposed without distortion-inthe grooves, the axial alignment of-the spindles -isassured-; and-since the rod may be several feet-long, alignment maybe-made without bringing the ends of the spindles together.

Lateral deviation inthe spindle alignment is unlikely ina carefully made and-carefullyused tool; but means are provided in one i oftheframe arms for a;minor correction if required.

Interposedin the-arm 5, preferably nearits connection with th'e link; is a swivel joint 33,- perm itting a small amount of twisting adjustment between the parts; oithe arm; Theadiacent ends of the armterminatein round plates 34 =with flat engagingsurfaces 36 locked together asbest shownin Figure 2, by screws 31 threadeddnto-one oi the plates and passing through-arcuateslpts 38 in the other plate. For stability: of the joint, a short stub journal 4| ,iS formed at the center onone of, the plates and seats in abearing in the otl'ier plate. Gage marks 42 on the peripheral suria'cepf the plates across the joint'between them, mark an aligned setting; Slight adjust: ment or the swivel joint afterloosening the clamp screws 31, will correct small lateral error inthe pindle. a n en th o ete a snment.being ob i e w ththe em of t e dj e ead xplaine nu inai i a -senio p c c n t measu e: men s h.iQ Xamp -a QQtf -3 inches the rame s vset. isnedto, feet and w ole i ches. themeas i smeni bein takenifrema ea er h mic me a inerl eadiaib onerat dioim cliidathe raction. ihe fina'set i ie. When the. tool is used for a relative ,settinisrtmoreor iess than a known but. unspecified value, such1,fo'r example as, acylinder bore .005" more than its piston, th e setting of the tool is based directly on the piston and the increase is added by the mi-, crometer setting.

What is claimed is:

1. A caliper comprising 'a pair of. armafi link for pivotally connecting the arms at their ends, a head block pivotally connected to the other end of each arm, a micrometer anvirarrangedin one of the blocks, a micrometer caliper head arranged in the other block, and means engaging both blocks for axially aligning the anvil and caliper head.

2. A caliper comprising a pair of arms, a link for pivotally connecting the arms at their ends, a head block pivotally connected to the other end of each arm, a micometer anvil arranged in one of the blocks, amicrometerflcaliper head arranged in, the other block, eachaof isaid blocks having a recess therein in alignment with the other when the anvil and caliper head are axially aligned, and an adjustment rod seating in said recesses for aligning the anvil and caliper head.

3.. A calipercomprising a pair of arms, a link for pivotallyponnecting the arms at their ends, a head blocktpivotally connected to the other end of each arm, a micrometer anvil arranged in one ofitheblockaamicrometer caliper head arranged in th e.other block, a swivel joint in one of said arms for correcting lateral misalignment of the anvil; and caliper head'in one-directionand means for correcting lateral misalignmentoii the anvil and caliper head in another direction.-

4. Acaliperzcomprising.-apairof arms, a link for; pivotallyv connecting the arms at their I ends, a. head. block .pivotally connected to the other end of each: arm, amicrometer anvil arranged in one of the blocks, a micrometer caliper head arranged the other block, means engaging both blocks for. axially: aligning theanvil and caliper head, and means for locking each pivotal connection to render the caliper rigid.

5;: A- caliper-comprising apairoi arms; a link for. pivotallyconnecting the arms at their ends, a headblock pivotallyconnected tetheother end of "each arm, a micrometer anvil arrangedin one of the blocks, amicrometer cali-per-head-arranged in=the other block;- each of said-blocks havinga recess therein in alignment with theother when the anvil and caliper headareaxially aligned, an adjustment rod seating 111"Sfiid'1'8CESS9SffOI' aligning the anvil and caliper head: and-means for dockingeachpivotal "connection to render the caliper rigid.

6. A long-span micrometer caliper comprising a pair of; arms, a head'block pivotal-ly mounted 'on one endof each-arm; a-micrometer-anvil arranged in one of the blockaamicrometer caliperhead arranged" in *the other block: means for axially aligning the anvil-and caliper-head, and .a link detachably and pivotally connectin ;the other ends of said-arms.

'7. A long-span micrometer caliper comprising alink having its ends bifurcated, an arm' detach-- ably and pivotally" mounted in each bifurcated endand-movable therein-through an arc of about 186; head-blocks'pivotally mounted on the, fr,ee endsof said arms; a micrometer anvilflj arranged in'one of the blocks,- a micrometer caliper head arranged-in the otherblocklandmeansfor axially aligning the anvil and caliper" head.

MARION JFL'OLOUGHIEINI G uardz'anofithe Person and jEstateof Ja'mes Ci OLouyivlz'flr v n:I1iccimpetent Person. 

